Abstract
The prognostic role of lymphadenectomy during surgery for oesophageal cancer is questioned. We aimed to test whether higher lymph node harvest increases the risk of early postoperative reoperation or mortality. A population-based cohort study including almost all patients who underwent resection for oesophageal cancer in Sweden in 1987-2010. Data were collected from medical records and well-established nationwide Swedish registries. The exposures were number of removed lymph nodes (primary) and number of node metastases (secondary). The main study outcome was reoperation/mortality within 30 days of primary surgery. Relative risks (RRs) with 95% confidence intervals (CIs) were calculated using Poisson regression, adjusted for age, sex, co-morbidity, neoadjuvant therapy, tumour stage, tumour histology, surgeon volume, and calendar period. Among 1,820 participants, the risk of reoperation/mortality did not increase with greater lymph node harvest (RR = 0.98, 95%CI 0.96-1.00, discrete variable) or with greater number of removed metastatic nodes (RR = 1.00, 95% CI 0.95-1.05, discrete variable). Similarly, in stratified analyses within pre-defined categories of tumor stage, surgeon volume and calendar period, increased number of removed nodes or node metastases did not increase the risk of reoperation/mortality. Lymphadenectomy during oesophageal cancer surgery is a safe procedure in the short term perspective.